Display device and method for driving the same

ABSTRACT

A method for driving a display device is performed by the display device. The method includes: displaying a first image including user convenience information through a display panel; generating sensing data corresponding to a fingerprint sensing area by using a photoelectric sensor; and determining whether a sensed fingerprint corresponding to the sensing data is a fake fingerprint by comparing expected sensing light illuminance information based on the first image with sensed light illuminance information of the sensing data. The first image includes a first color pattern in the fingerprint sensing area of the display panel. A fake-determination image pattern includes the first color pattern and a second color pattern different from the first color pattern.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority under 35 U.S.C. § 119(a) toKorean patent application 10-2020-0076007 filed on Jun. 22, 2020, in theKorean Intellectual Property Office, the entire disclosure of which isincorporated by reference.

TECHNICAL FIELD

The present disclosure generally relates to a display device and amethod for driving the same, and more particularly, to a display deviceincluding a photoelectric sensor and a method for driving the same.

RELATED ART

As the use of display devices in smartphones and tablet PCs hasincreased in many fields, a biometric authentication method using afingerprint of a user has been widely used. In order to provide afingerprint sensing function, a fingerprint sensor may be built into adisplay device or be attached to the top and/or the bottom of thedisplay device. The display device integrated with the fingerprintsensor is referred to as a Fingerprint on Display (FoD).

The FoD may be configured as, for example, a photosensitive type sensor.The photosensitive type FoD may use, as a light source, a light emittingdevice provided in a pixel, and include a photoelectric sensor array.The photoelectric sensor array may be implemented as, for example, aCMOS Image Sensor (CIS).

Regular personal authentication using such a fingerprint sensor may beused in fields which require security, such as e-commerce using mobiledevices, financial transactions, security of electronic devices, andapproval of use. Hence, it is not only important to achieve highaccuracy of fingerprint recognition, but also to effectively identify aforged or fake fingerprint.

SUMMARY

Embodiments provide a display device for detecting a fake fingerprint byanalyzing light which is diffused from skin and then sensed in anon-emission area of a fingerprint sensing area. Embodiments alsoprovide a method for driving the display device.

In accordance with an exemplary embodiment of the present disclosure,there is provided a display device including: a display panel having aplurality of pixels, the display panel displaying a first imageincluding user convenience information; a photoelectric sensor disposedon one surface of the display panel to sense light; and a fingerprintdetector configured to determine whether a sensed fingerprintcorresponding to a sensing signal supplied from the photoelectric sensoris a fake fingerprint, based on the sensing signal, wherein the firstimage includes a first color pattern in a fingerprint sensing area ofthe display panel, and wherein a fake determination image patternincludes the first color pattern and a second color pattern differentfrom the first color pattern.

The user convenience information may include an indication imageindicating the fingerprint sensing area. The indication image mayinclude the first color pattern.

A luminance of the first color pattern may be lower than that of thesecond color pattern.

The fingerprint detector may determine whether the sensed fingerprint isa fake fingerprint by analyzing a light illuminance sensed in a firstarea in which the first color pattern is displayed.

When the light illuminance sensed in the first area is smaller than apredetermined first reference light illuminance, the fingerprintdetector may determine that the sensed fingerprint is a fakefingerprint.

When a light illuminance sensed in a second area in which the secondcolor pattern is displayed is greater than a predetermined secondreference light illuminance, the fingerprint detector may determine thatthe sensed fingerprint is a fake fingerprint.

The fake-determination image pattern may include a first emission area,a first non-emission area, and a second emission area, which aresequentially arranged along a first direction. The first color patternmay include the first non-emission area, and the second color patternmay include the first emission area and the second emission area. Awidth of the first non-emission area in the first direction may be setsuch that a light illuminance sensed in the first non-emission area issubstantially maximized.

The fake-determination image pattern may further include a secondnon-emission area and a third emission area, which are sequentiallyarranged along the first direction with respect to the second emissionarea. A width of the second non-emission area may be equal to that ofthe first non-emission area, and a width of the second emission area maybe greater than or equal to that of the first non-emission area.

The first image may include a fingerprint pattern imitating afingerprint. The fingerprint pattern may include the first colorpattern.

The fingerprint detector may control the fake-determination imagepattern of the fingerprint sensing area of the display panel, which isused for fingerprint sensing, and perform fingerprint authentication onthe sensed fingerprint, based on the sensing signal.

The fingerprint detector may include: a pattern controller configured togenerate the fake-determination image pattern such that the first colorpattern is included in the fingerprint sensing area; a fake fingerprintdetector configured to perform fake fingerprint determination bycomparing first sensing data corresponding to the second color patternof the fake-determination image pattern and second sensing datacorresponding to the first color pattern of the fake-determination imagepattern with light illuminance information set corresponding to thefake-determination image pattern; and a fingerprint analyzer configuredto perform the fingerprint authentication by comparing third sensingdata corresponding to the fingerprint sensing area except the firstcolor pattern with registered fingerprint data.

The fingerprint detector may include: a pattern controller configured togenerate the fake-determination image pattern such that the first colorpattern is included in the fingerprint sensing area; a fake fingerprintdetector configured to perform fake fingerprint determination bycomparing first sensing data corresponding to the second color patternof the fake-determination image pattern and second sensing datacorresponding to the first color pattern of the fake-determination imagepattern with light illuminance information set corresponding to thefake-determination image pattern; and a fingerprint analyzer configuredto perform the fingerprint authentication by comparing third sensingdata corresponding to the fingerprint sensing area with registeredfingerprint data.

The fake fingerprint detector may compare a first light pattern as anexpected sensing light illuminance of a second area of the fingerprintsensing area, which is included in the light illuminance information,with a light profile of the first sensing data, and compare a secondlight pattern as an expected sensing light illuminance of a first areaof the fingerprint sensing area, which is included in the lightilluminance information, with a light profile of the second sensingdata. The first color pattern may be displayed in the first area, andthe second color pattern may be displayed in the second area.

When an accordance rate between the first sensing data and the firstlight pattern and an accordance rate between the second sensing data andthe second light pattern are equal to or greater than a predeterminedthreshold value, the fake fingerprint detector may determine that thesensed fingerprint is a real fingerprint.

When at least one of the accordance rate between the first sensing dataand the first light pattern and the accordance rate between the secondsensing data and the second light pattern is less than a predeterminedthreshold value, the fake fingerprint detector may determine that thesensed fingerprint is a fake fingerprint.

The fingerprint detector may further include: a memory configured tostore the light illuminance information corresponding to thefake-determination image pattern and the registered fingerprint data;and a use approval determiner configured to finally determine whetheruse of the display device is to be approved, based on a result of thefake fingerprint determination and a result of the fingerprintauthentication.

The pattern controller may randomly change the fake-determination imagepattern displayed on the display panel in a predetermined period.

The pattern controller may generate the fake-determination image patternin a first period, and suspend the generation of the fake-determinationimage pattern in a second period.

The fake fingerprint detector may perform the fake fingerprintdetermination by using the first sensing data and the second sensingdata, which are sensed in the first period. The fingerprint analyzer mayperform the fingerprint authentication by using the third sensing datasensed in the second period.

The fingerprint analyzer may compare an accordance rate between aportion corresponding to the second color pattern in the registeredfingerprint data and the third sensing data.

In accordance with an exemplary embodiment of the present disclosure,there is provided a method for driving a display device, the methodincluding: displaying a first image including user convenienceinformation through a display panel; generating sensing datacorresponding to a fingerprint sensing area by using a photoelectricsensor; and determining whether a sensed fingerprint corresponding tothe sensing data is a fake fingerprint by comparing expected sensinglight illuminance information based on the first image with sensed lightilluminance information of the sensing data, wherein the first imageincludes a first color pattern in the fingerprint sensing area of thedisplay panel, and wherein a fake-determination image pattern includesthe first color pattern and a second color pattern different from thefirst color pattern.

The user convenience information may include an indication imageindicating the fingerprint sensing area. The indication image mayinclude the first color pattern.

A luminance of the first color pattern may be lower than that of thesecond color pattern.

The determining of whether the sensed fingerprint is the fakefingerprint may include: comparing a first light pattern as an expectedsensing light illuminance of a second area of the fingerprint sensingarea, which is included in the light illuminance information, with thefirst sensing data, and comparing a second light pattern as an expectedsensing light illuminance of a first area of the fingerprint sensingarea, which is included in the light illuminance information, with thesecond sensing data; and determining that the sensed fingerprint is areal fingerprint, when an accordance rate between the first sensing dataand the first light pattern and an accordance rate between the secondsensing data and the second light pattern are equal to or greater than apredetermined threshold value. The first color pattern may be displayedin the first area, and the second color pattern may be displayed in thesecond area.

The method may include determining that the sensed fingerprint is a fakefingerprint, when at least one of the accordance rate between the firstsensing data and the first light pattern and the accordance rate betweenthe second sensing data and the second light pattern is less than apredetermined threshold value.

When the display panel is power-on, the first image may be displayedbased on the power-on of the display panel.

The display panel may display a general image having a first refreshrate in a first mode, and display a power-saving image having a secondrefresh rate smaller than the first refresh rate in a second mode. Thepower-saving image may include the first image.

The method may further include displaying a second image in which lightis emitted in the entire fingerprint sensing area, based on a touchinput.

The method may further include: performing fingerprint authentication bycomparing the sensing data with registered fingerprint data; anddetermining whether use of display device is to be approved, based on aresult of the fingerprint authentication and a result of the fakefingerprint determination.

The performing of the fingerprint authentication may include: comparingan accordance rate between a portion corresponding to the second colorpattern in the registered fingerprint data and third sensing data; anddetermining that the sensed fingerprint accords with the registeredfingerprint data, when the accordance rate is a predetermined thresholdvalue or more. The second color pattern may be displayed in the secondarea.

The determining of whether the use of the display device is to beapproved may include approving the use of the display device, when thesensing data and the registered fingerprint data accord with each other,and the sensed fingerprint is a real fingerprint.

The determining of whether the use of the display device is to beapproved includes disapproving the use of the display device regardlessof whether the sensing data and the registered fingerprint data accordwith each other, when it is determined that the sensed fingerprint is afake fingerprint.

In accordance with still an exemplary embodiment of the presentdisclosure, there is provided a display device including: a displaypanel including a plurality of pixels, the display panel displaying afirst image including user convenience information; a photoelectricsensor disposed on one surface of the display panel to sense light; anda fingerprint detector configured to determine whether a sensedfingerprint corresponding to a sensing signal supplied from thephotoelectric sensor is a fake fingerprint, based on the sensing signal,wherein the first image includes a fake-determination image pattern in afingerprint sensing area, and the fake-determination image patternincludes a first pattern having a first planar shape.

The user convenience information may include an indication imageindicating the fingerprint sensing area. The indication image mayinclude the fake-determination image pattern.

When a touch input occurs in the fingerprint sensing area, a color orluminance of the fake-determination image pattern may be reversed, andthe first planar shape of the first pattern need not be changed.

In accordance with still an exemplary embodiment of the presentdisclosure, a fingerprint sensor includes: a first plurality of displaypixels configured to emit an image pattern; a second plurality ofphotoelectric sensor pixels disposed under said first plurality ofdisplay pixels and configured to sense reflected illuminance responsiveto said image pattern and provide a sensing signal based on saidreflected illuminance; and a fingerprint detector configured todetermine whether a sensed fingerprint corresponding to said sensingsignal is indicative of a fake fingerprint, based on said image pattern,said sensing signal, and characteristics of at least one realmulti-layered fingerprint, wherein said image pattern includes a firstcolor pattern and a second color pattern different from said first colorpattern.

The fingerprint sensor may have at least some of said second pluralityof photoelectric sensor pixels temporally disposed under said firstcolor pattern configured to substantially sense illuminance reflected bysaid sensed fingerprint based on luminance of said second color patternas temporally emitted by at least some of said first plurality ofdisplay pixels.

The fingerprint sensor may have said first and second color patternsdisplayed adjacent to each other at a scale smaller than that of afingerprint. The fingerprint sensor may have said first color patternwith lower luminance than said second color pattern. The fingerprintsensor may have said first and second color patterns concurrentlydisplayed by the first plurality of display pixels and sensed by thesecond plurality of photoelectric sensor pixels.

In the display device including the photoelectric sensor and the methodfor driving the same in accordance with the present disclosure, a fakefingerprint can be detected by analyzing a light illuminance or lightpattern in the non-emission area included in the fake-determinationimage pattern. Accordingly, the accuracy and reliability of fingerprintdetection can be optimized without substantially increasingmanufacturing costs and/or additional configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments will now be described more fully hereinafter withreference to the accompanying drawings; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the exemplary embodiments to those skilled in theart.

In the drawing figures, dimensions may be exaggerated for clarity ofillustration. It will be understood that when an element is referred toas being “between” two elements, it can be the only element between thetwo elements, or one or more intervening elements may also be present.Like reference numerals may refer to like elements throughout thedrawings that follow, in which:

FIG. 1A is a block diagram schematically illustrating a display devicein accordance with embodiments of the present disclosure;

FIG. 1B is a block diagram schematically illustrating another example ofthe display device shown in FIG. 1A;

FIG. 2A is a sectional view diagram illustrating an example of thedisplay device shown in FIG. 1A;

FIG. 2B is a sectional view diagram illustrating another example of thedisplay device shown in FIG. 1A;

FIG. 3A is a block diagram illustrating an example of a configuration ofa photoelectric sensor and a fingerprint detector, which are included inthe display device shown in FIG. 1A;

FIG. 3B is a circuit diagram illustrating an example of a sensor pixelincluded in the photoelectric sensor shown in FIG. 3A;

FIG. 4 is a schematic diagram illustrating an example of a path of lightincident into skin of a user;

FIG. 5A is a schematic diagram illustrating light detected from afingerprint sensing area of a display panel of the display device shownin FIG. 1A;

FIG. 5B is a graphical diagram illustrating light illuminanceinformation sensed corresponding to portion I-I′ shown in FIG. 5A;

FIG. 5C is a schematic diagram illustrating properties of lightsreflected by a real fingerprint and a fake fingerprint according to afake-determination image pattern shown in FIG. 5A;

FIGS. 6A and 6B are block diagrams illustrating an example of thefingerprint detector included in the display device shown in FIG. 1A;

FIG. 7A is a schematic diagram illustrating an example of an imagedisplayed on the display panel of the display device shown in FIG. 1A;

FIG. 7B is a schematic diagram illustrating various example of afake-determination image pattern included in the image shown in FIG. 7A;

FIG. 8 is a hybrid diagram illustrating a size of a first color patternincluded in the fake-determination image pattern shown in FIG. 7B;

FIGS. 9A to 9D are timing diagrams illustrating an operation of thedisplay device shown in FIG. 1A;

FIGS. 10A and 10B are schematic diagrams illustrating an operation ofthe display device shown in FIG. 1A;

FIG. 11 is a flowchart diagram illustrating a method for driving thedisplay device in accordance with embodiments of the present disclosure;

FIG. 12 is a flowchart diagram illustrating an example of the methodshown in FIG. 11 ;

FIG. 13 is a flowchart diagram illustrating another example of themethod shown in FIG. 11 ;

FIG. 14 is a flowchart diagram illustrating still another example of themethod shown in FIG. 11 ;

FIG. 15 is a flowchart diagram illustrating still another example of themethod shown in FIG. 11 ; and

FIG. 16 is a flowchart diagram illustrating still another example of themethod shown in FIG. 11 .

DETAILED DESCRIPTION

Hereinafter, exemplary embodiments may be described in detail withreference to the accompanying drawings so that those skilled in the artmay easily practice embodiments the present disclosure. The presentdisclosure may be implemented in various different forms and is notlimited to the exemplary embodiments described in the presentspecification.

A part or parts irrelevant to the description may be omitted to clearlydescribe the present disclosure, and the same or similar constituentelements may be designated by the same or similar reference numeralsthroughout the specification. Therefore, the same or similar referencenumerals may be used in different drawings to identify the same orsimilar elements.

In addition, the sizes and thicknesses of each component illustrated inthe drawings are arbitrarily shown for better understanding and ease ofdescription, but the present disclosure is not limited thereto.Thicknesses of several portions and regions may be exaggerated for clearexpressions.

FIG. 1A schematically illustrates a display device in accordance with anembodiment of the present disclosure. FIG. 1B schematically illustratesan example of the display device shown in FIG. 1A.

For convenience, although a case where a display panel 100 and a driver200 are separated from each other is illustrated in FIGS. 1A and 1B, thepresent disclosure is not limited thereto. More specifically, the wholeor a portion of the driver 200 may be integrally implemented with thedisplay panel 100 such as on the display panel 100.

Referring to FIGS. 1A and 1B, the display device 1000 may include thedisplay panel 100 and the driver 200. The driver 200 may include a paneldriver 210 and a fingerprint detector 220.

The whole or at least a portion of the display device 1000 may haveflexibility, such as in bendable, rollable and/or foldable embodiments.

The display panel 100 includes a display area AA and a non-display areaNA. The display area AA is an active area including a plurality ofpixels PXL, which may include and/or be referred to as sub-pixels. Invarious embodiments, each of the pixels PXL may include at least onelight emitting device. The display device 1000 drives the pixels PXL,corresponding to image data input from the outside, thereby displayingan image in the display area AA.

In an embodiment, the display area AA may include a fingerprint sensingarea FSA. The fingerprint sensing area FSA may include at least somepixels PXL among the plurality of pixels PXL provided in the displayarea AA.

In an embodiment, as shown in FIG. 1A, at least a portion of the displayarea AA may be set as the fingerprint sensing area FSA.

In an embodiment, as shown in FIG. 1B, the entire display area AA may beset as the fingerprint sensing area FSA. When fingerprint sensing isperformed, a fingerprint sensing operation may be performed on only aportion of the FSA at which a touch of a user is substantially made.

Although an example is shown in which only one fingerprint sensing areaFSA is formed in the display area AA, as illustrated in FIG. 1A, thepresent disclosure is not limited thereto. For example, a plurality offingerprint sensing areas FSA arranged regularly or irregularly may beformed in the display area AA.

Also, although an example in which the fingerprint sensing area FSA isformed in at least a portion of the display area AA is illustrated inFIG. 1A, the present disclosure is not limited thereto. That is, invarious embodiments, the display area AA and the fingerprint sensingarea FSA may be provided to partially overlap with each other.

The non-display area NA may be an area disposed at the periphery of thedisplay area AA, and may be referred to as a non-active area. Forexample, the non-display area NA may include a line area, a pad area,various dummy areas, and the like.

In an embodiment, the display device 1000 may further include aplurality of sensor pixels SPXL provided in the fingerprint sensing areaFSA. The sensor pixels SPXL may be configured as a sensor for sensinglight. In an embodiment, when light emitted from a light source or pixelPXL provided in the display device 1000 is reflected by a finger of auser, the sensor pixels SPXL may sense the reflected light and output anelectrical signal such as a voltage signal corresponding to thereflected light. The electrical signal may be transferred to the driver200 and/or the fingerprint detector 220, which may be described ingreater detail, infra, to be used for fingerprint sensing. Hereinafter,although an example in which the sensor pixels SPXL are used forfingerprint sensing is described in the present disclosure, one or moreof the sensor pixels SPXL may be used to perform various functions of atouch sensor, a scanner, or the like.

When the sensor pixels SPXL are arranged in the fingerprint sensing areaFSA, the sensor pixels SPXL may overlap with the pixels PXL or bedisposed at the periphery of at least some of the pixels PXL. Forexample, some or all of the sensor pixels SPXL may overlap with thepixels PXL or be disposed between the pixels PXL. In variousembodiments, the sensor pixels SPXL and the pixels PXL may have the samesize or different sizes. The relative size and arrangement between thesensor pixels SPXL and the pixels PXL are not particularly limited.

When the sensor pixels SPXL are disposed adjacent to the pixels PXL oroverlap with the pixels PXL for at least a portion thereof, the sensorpixels SPXL may use, as a light source, the light emitting deviceprovided in each pixel PXL. Therefore, the sensor pixels SPXL along withthe light emitting devices provided in the pixels PXL may constitute aphotosensitive type fingerprint sensor. When a display device having abuilt-in fingerprint sensor is configured by using the pixels PXL aslight sources, without any external light source, the module thicknessof the photosensitive type fingerprint sensor and the display devicehaving the same can be relatively thin.

In various embodiments, the sensor pixels SPXL may be arranged on theother surface, such as a rear surface, facing one surface, such as afront surface, on which an image is displayed between both the surfacesof the display panel 100. However, the present disclosure is not limitedthereto.

The driver 200 may drive the display panel 100. For example, the driver200 may output a data signal DS corresponding to image data to thedisplay panel 100. Also, the driver 200 may output a driving signal forthe sensor pixels SPXL, and receive electrical signals, such as asensing signal SS, received from the sensor pixels SPXL. The driver 200may detect a fingerprint shape or pattern of a user by using theelectrical signals, and/or detect a fake fingerprint.

In various embodiments, the driver 200 may include the panel driver 210and the fingerprint detector 220. For convenience of description,although a case where the panel driver 210 and the fingerprint detector220 are separated from each other is illustrated in FIGS. 1A and 1B, thepresent disclosure is not limited thereto. For example, at least aportion of the fingerprint detector 220 may be integrated with the paneldriver 210 or operate in connection with the panel driver 210.

The panel driver 210 may supply a data signal DS corresponding to imagedata to the pixels PXL while sequentially scanning the pixels PXL of thedisplay area AA. The display panel 100 may display an imagecorresponding to the image data.

In an embodiment, the panel driver 210 may supply a driving signal DSfor fingerprint sensing to the pixels PXL. The driving signal may beprovided to allow the pixels PXL to operate as light sources for thesensor pixels SPXL by emitting light of one or more colors. Therefore,the driving signal for fingerprint sensing may be provided to pixels PXLprovided in a specific area of the display panel 100, such as but notlimited to pixels PXL provided in the fingerprint sensing area FSA.

In an embodiment, image data corresponding to the fingerprint sensingarea FSA may be provided or controlled by the fingerprint detector 220.For example, in a fingerprint sensing operation, the fingerprintdetector 220 may provide the panel driver 210 with image datacorresponding to a fake-determination image pattern IPD to be displayedin the fingerprint sensing area FSA, or provide the panel driver 210with compensation data and/or a control signal which corresponds to thefake-determination image pattern IPD.

In addition, the driving signal for fingerprint sensing may be providedby the fingerprint detector 220.

The fingerprint detector 220 may transfer, to the sensor pixels SPXL, adriving signal such as a driving voltage for driving the sensor pixelsSPXL, and detect a fingerprint of a user based on electrical signalsreceived from the sensor pixels SPXL. For example, the fingerprintdetector 220 may perform fingerprint authentication and fake fingerprintdetermination, including determination of whether the detectedfingerprint is a fake fingerprint, based on a sensing signal SS suppliedfrom the sensor pixels SPXL, which may be photoelectric sensors or thelike.

In an embodiment, the fingerprint detector 220 may control afake-determination image pattern of the fingerprint sensing area FSA,and perform fingerprint authentication and fake fingerprintdetermination, based on a sensing signal SS supplied from aphotoelectric sensor including the sensor pixel SPXL, and the like. Thefake-determination image pattern may include a first color pattern, suchas a relatively non-emission pattern for a non-emission area or firstarea, and a second color pattern such as an emission pattern for anemission area or second area. A luminance of the first color pattern maybe lower than that of the second color pattern. An area in which thefirst color pattern having a relatively low luminance is displayed maybe defined as a non-emission area, and an area in which the second colorpattern having a relatively high luminance is displayed may be definedas an emission area. The fingerprint detector 220 may determine whetherthe sensed fingerprint is a fake fingerprint by analyzing a lightilluminance sensed in the non-emission area.

For example, when the light illuminance sensed in the non-emission areais smaller than a predetermined reference light illuminance, thefingerprint detector 220 may determine that the sensed fingerprint is afake fingerprint. On the contrary, when the light illuminance sensed inthe non-emission area is equal to or greater than the predeterminedreference light illuminance, the fingerprint detector 220 may determinethat the sensed fingerprint is a real biometric fingerprint.

FIG. 2A is a sectional view illustrating an example of the displaydevice shown in FIG. 1A or 1B.

Specifically, FIG. 2A illustrates an example of a section in thefingerprint sensing area FSA of the display device 1000 shown in FIGS.1A and/or 1B.

Referring to FIGS. 1A to 2A, the display device 1000 may include thedisplay panel 100 in the fingerprint sensing area FSA and aphotoelectric sensor PS disposed on a surface of the display panel 100.The display device 1000 may also include a substrate SUB, and a circuitelement layer BPL, a light emitting device layer LDL, a first protectivelayer PTL1, a first adhesive layer ADL1, and a window WIN, which aresequentially disposed on a first surface (e.g., an upper surface) of thesubstrate SUB. The display device 1000 may also include a secondadhesive layer ADL2 and a second protective layer PTL2, which aresequentially disposed on a second surface (e.g., a lower surface) of thesubstrate SUB in the fingerprint sensing area FSA.

The substrate SUB is a base substrate of the display panel 100, and maybe a substantially transparent transmissive substrate. The substrate SUBmay be a rigid substrate including glass or tempered glass, or aflexible substrate made of plastic or the like. However, the material ofthe substrate SUB is not limited thereto, and the substrate SUB may bemade of various materials.

The circuit element layer BPL may be disposed on the first surface ofthe substrate SUB, and include at least one conductive layer. Forexample, the circuit element layer BPL may include a plurality ofcircuit elements constituting pixel circuits of the pixels PXL and linesfor supplying various power sources and signals for driving the pixelsPXL. The circuit element layer BPL may include various types of circuitelements such as at least one transistor and at least one capacitor, anda plurality of conductive layers for constituting lines connected to thecircuit elements. The circuit element layer BPL may also include atleast one insulating layer provided between the plurality of conductivelayers.

The light emitting device layer LDL may be disposed on one surface ofthe circuit element layer BPL. The light emitting device layer LDL mayinclude a plurality of light emitting devices LD connected to thecircuit elements and/or the lines of the circuit element layer BPLthrough contact holes, and the like. In an embodiment, at least one ofthe plurality of light emitting devices LD may be provided in each pixelPXL. For example, the light emitting device LD may be configured as anorganic light emitting diode or an inorganic light emitting diode suchas a micro light emitting diode or a quantum dot light emitting diode.Also, the light emitting device LD may be a light emitting device madeof a combination of an organic material and an inorganic material.Further, each of the pixels PX includes a single light emitting deviceLD. Alternatively, in another embodiment, each of the pixels PX mayinclude a plurality of light emitting devices, and the plurality oflight emitting devices may be coupled in parallel to each other, becoupled in series to each other, or be coupled in a hybrid series and/orparallel combination to each other.

Each of the pixels PXL may include circuit elements disposed in thecircuit element layer BPL and at least one light emitting device LDdisposed in the light emitting device layer LDL such as on the top ofthe circuit element layer BPL.

The first protective layer PTL1 may be disposed on the top of the lightemitting device layer LDL to cover the display area AA. The firstprotective layer PTL1 may include an encapsulating member such as a thinfilm encapsulation (TFE) layer or an encapsulation substrate, andadditionally include a protective film, and the like, in addition to theencapsulating member.

The first adhesive layer ADL1 is disposed between the first protectivelayer PTL1 and the window WIN to allow the first protective layer PTL1and the window WIN to be coupled to each other. The first adhesive layerADL1 may include a transparent adhesive such as an optically clearadhesive (OCA), and include various adhesive materials in addition tothe transparent adhesive.

The window WIN is a protective member disposed at a modular uppermostportion of the display device 1000 including the display panel 100, andmay be a substantially transparent transmissive substrate. The windowWIN may have a multi-layered structure selected from a glass substrate,a plastic film, and a plastic substrate, or the like. The window WIN mayinclude a rigid or flexible substrate, and the material constituting thewindow WIN is not particularly limited.

In various embodiments, the display device 1000 may further include apolarizing plate, an anti-reflective layer, and/or a touch sensor layersuch as a touch electrode layer. For example, the display device 1000may further include a polarizing plate and/or a touch sensor layer,disposed between the first protective layer PTL1 and the window WIN.

The touch sensor layer may include a plurality of sensing electrodes orsensing cells. The driver 200 described with reference to FIG. 1A maysense whether a touch input occurs and a position or coordinate of thetouch input, based on a change in capacitance between the sensingelectrodes.

The second protective layer PTL2 may be disposed on the other surface ofthe substrate SUB. The second protective layer PTL2 may be coupled tothe substrate SUB by the second adhesive layer ADL2.

The second adhesive layer ADL2 may allow the substrate SUB and thesecond protective layer PTL2 to be firmly coupled or attached to eachother. The second adhesive layer ADL2 may include a transparent adhesivesuch as an OCA. The second adhesive layer ADL2 may include a pressuresensitive adhesive (PSA) in which an adhesive material acts whenpressure is applied for allowing the second adhesive layer ADL2 to beadhered to an adhesive surface.

The second protective layer PTL2 prevents oxygen and moisture from beingintroduced thereto from the outside, and may be provided in the form ofa single layer or a multi-layer structure. The second protective layerPTL2 may be configured in a film form, and further ensure flexibility ofthe display panel 100. The second protective layer PTL2 may be coupledto the photoelectric sensor PS through another adhesive layer includinga transparent adhesive such as an OCA.

In various embodiments, a selective light blocking film may be furtherprovided on the bottom of the second protective layer PTL2. Theselective light blocking film blocks a specific frequency region, suchas, for example, ultraviolet light in external light introduced to thedisplay device 1000, to prevent the corresponding light from beingincident into sensor pixels SPXL of the photoelectric sensor PS.Although a case where the selective light blocking film is furtherprovided on the bottom of the second protective layer PTL2 is describedabove, the present disclosure is not limited thereto.

The photoelectric sensor PS is attached to the other surface, such asthe rear and/or bottom surface, of the display panel 100 through anadhesive or the like to overlap with at least one area of the displaypanel 100. For example, the photoelectric sensor PS may be disposed tooverlap with the display panel 100 in the fingerprint sensing area FSA.The photoelectric sensor PS may include a plurality of sensor pixelsSPXL distributed at a predetermined resolution and/or a predetermineddistance.

In an embodiment, an optical system which provides a light path byconcentrating light emissions advancing toward the photoelectric sensorPS may be provided on the photoelectric sensor PS. In the opticalsystem, a width of a light transmitting part for guiding light may bedetermined by considering sensing precision and light conversionefficiency. The concentration ratio of lights incident onto thephotoelectric sensor PS may be optimized by the optical system. In someembodiments, the optical system may be formed of optical fiber, silicon,or the like.

The sensor pixels SPXL may have an appropriate number, an appropriatesize, and an appropriate arrangement such that a fingerprint image to beidentifiable from electrical signals output by the sensing pixels SPXLcan be generated. The distance between the sensor pixels SPXL may bedensely set such that reflected light reflected from an object to beobserved, such as a fingerprint or the like but not limited thereto, canbe incident into at least two adjacent sensor pixels SPXL.

The sensor pixels SPXL may output a corresponding electrical signal,such as but not limited to a voltage signal, by sensing external light.Reflected light received at the respective sensor pixels SPXL may haveoptical properties such as frequencies, wavelengths, sizes, and thelike, caused by valleys and ridges of a fingerprint formed on a fingerof a user. Therefore, the sensor pixels SPXL may output a sensing signalSS having different electrical characteristics corresponding to theoptical properties of the reflected light.

In an embodiment, the sensing signal SS output by the sensor pixels SPXLmay be converted into image data by the fingerprint detector 220, and beused for fingerprint identification and fingerprint authentication ofthe user. In addition, the fingerprint detector 220 may analyze anoptical profile for a portion of the sensing signal SS, and detect afake fingerprint, based on the analyzed optical profile.

FIG. 2B is a sectional view illustrating another example of the displaydevice shown in FIG. 1A. Specifically, FIG. 2B illustrates anotherexample of the section in the fingerprint sensing area FSA of thedisplay device 1000 shown in FIGS. 1A and 1B.

Referring to FIGS. 1A, 2A, and 2B, in another embodiment, the displaydevice 1000 may further include a light blocking layer PHL including pinholes PIH. The light blocking layer PHL may be disposed in the displaypanel 100 or between the display panel 100 and the sensor pixels SPXL,and may block some of the light directed towards the sensor pixels SPXL.For example, some of the light incident upon the light blocking layerPHL may be blocked, and the remaining light may reach the sensor pixelsSPXL under the light blocking layer PHL by passing through the pin holesPIH. The pin holes PIH operate as an optical system, and may be usedtogether with another optical system.

An exemplary embodiment fingerprint sensor may include display pixelsPXL configured to emit an image pattern; photoelectric sensor pixelsSPXL disposed under the display pixels and configured to sense reflectedilluminance responsive to the image pattern and provide a sensing signalSS based on the reflected illuminance; and the fingerprint detector 220configured to determine whether a sensed fingerprint corresponding tothe sensing signal is indicative of a fake fingerprint, based on theimage pattern, the sensing signal, and characteristics of at least onereal multi-layered fingerprint, where the image pattern may include afirst color pattern CP1 and a second color pattern CP2 different fromthe first color pattern.

Each of the pin holes PIH may mean an optical hole, and provide a typeof light passageway. For example, the pin hole PHI may be a lightpassageway having the smallest size or area among light passagewaysdisposed when layers of the display device 1000 overlap with each other,on a path along which reflected light passes through the display panel100 in an oblique direction or vertical direction and then is incidentupon the sensor pixels SPXL.

The pin holes PIH may have a predetermined width, such as, for example,a width w in a range of about 5 μm to about 20 μm. In this manner, thewidth of an optical opening area, which is to be secured in each layerof the display device 1000, may gradually increase as becoming moredistant from the light blocking layer PHL, such as where approaching thetop and bottom of the light blocking layer PHL.

The width or diameter of the pin holes PIH may be set to about ten timeslonger than the wavelength of reflected light, such as about 4 μm or 5μm or more so as to prevent diffraction of light. The width of the pinholes PIH may also be set to a size large enough to prevent image blurand to more clearly sense the shape of a fingerprint. For example, thewidth of the pin holes PIH may be set to about 15 μm or less. However,the present disclosure is not limited thereto, and the width of the pinholes PIH may be changed depending on the wavelength band or bands ofreflected light and/or the thickness of a module for each layer.

Only light reflected from the putative fingerprint and passing throughthe pin holes PIH may reach the sensor pixels SPXL. A phase of lightreflected from a fingerprint by the pin hole PIH having a relativelynarrow width and a phase of an image formed in the photoelectric sensorPS may have a difference of 180 degrees, for example.

The sensor pixels SPXL may output a sensing signal SS, such as a voltagesignal corresponding with reflected light received thereto.

However, this is merely illustrative, and the configuration,arrangement, driving method, and the like of a photoelectric sensor fordetecting light reflected from a fingerprint are not limited to thephotoelectric sensor PS shown in FIG. 2A or 2B.

FIG. 3A illustrates an example of a configuration of the photoelectricsensor and the fingerprint detector, which may be included in thedisplay device shown in FIG. 1A.

Referring to FIGS. 1A and 3A, the photoelectric sensor PS may include anarray of sensor pixels SPXL. In an embodiment, the sensor pixels SPXLmay be arranged in a two-dimensional array, but the present disclosureis not limited thereto. Each of the sensor pixels SPXL may include aphotoelectric device which converts incident light into electric chargesaccording to an illuminance of the light.

The fingerprint detector 220 may include a horizontal driver 221, avertical driver 222, and a controller 223.

The horizontal driver 221 may be connected to the sensor pixels SPXLthrough driving lines H1 to Hn. The horizontal driver 221 may beconfigured as a shift register, an address decoder, or the like. Invarious embodiments, the horizontal driver 221 may apply a drivingsignal to drive selected sensor pixels SPXL among the sensor pixelsSPXL. For example, the horizontal driver 221 may apply a driving signalto a sensor pixel row.

Sensor pixels SPXL selected and driven by the horizontal driver 221sense light by using photoelectric devices provided therein, and outputan electrical signal, such as sensing signal SS, which may be a voltagesignal corresponding to the sensed light. The output electrical signalmay be an analog signal.

The vertical driver 222 may be connected to the sensor pixels SPXLthrough signal lines V1 to Vm. The vertical driver 222 may performprocessing on a signal output from the sensor pixels SPXL.

For example, the vertical driver 222 may perform Correlated DoubleSampling (CDS) processing for removing noise from an electrical signalreceived thereto. The vertical driver 222 may also convert an analogsignal received from the sensor pixel SPXL into a digital signal. In anembodiment, an analog-digital converter may be provided for each sensorpixel column, to process in parallel analog signals received from thesensor pixel columns.

The controller 223 may control the horizontal driver 221 and thevertical driver 222.

In an embodiment, the controller 223 may generate image datacorresponding to the sensing signal SS received from the vertical driver222, and, perform processing on the generated image data. In anembodiment, the controller 223 may detect a fingerprint from theprocessed image data, or authenticate the detected fingerprint and/ortransmit the detected fingerprint to the outside. For example, thecontroller 223 may include at least some of components included in afingerprint detector 220 shown in FIGS. 6A and 6B, or perform functionsof at least some of the components.

However, this is merely illustrative, and generation of image data andfingerprint detection need not be performed by the controller 223 butmay be performed by an external host processor, or the like.

FIG. 3B is a circuit example of the sensor pixel included in thephotoelectric sensor shown in FIG. 3A.

In FIG. 3B, a sensor pixel SPXL disposed on an x^(th) sensor pixel rowand an y^(th) sensor pixel column is illustrated, where x and y arepositive integers.

Referring to FIGS. 3A and 3B, the sensor pixel SPXL includes aphotoelectric diode PD as a non-limiting example of the photoelectricdevice, a transmission transistor TRTX, a reset transistor TRRX, and anamplification transistor TRAMP. In FIG. 3B, an example in which thetransistors are implemented as N-type transistors is illustrated,without limitation thereto. However, in various embodiments, at leastsome of the transistors may be implemented as P-type transistors, andcorresponding to this, the circuit structure of the sensor pixel SPXLmay be variously modified.

An anode electrode of the photoelectric diode PD may be grounded. Thetransmission transistor TRTX is connected between a cathode electrode ofthe photoelectric diode PD and a first node N1, and a gate electrode ofthe transmission transistor TRTX is connected to the horizontal driver221. The transmission transistor TRTX is turned on when a driving signalis applied through a driving line Hx, to operate as a transmission gateunit that transfers electric charges converted from light in thephotoelectric diode PD to the first node N1 as an electric chargevoltage converter.

The reset transistor TRRX is connected between a reset power sourceV_(RESET) and the first node N1, and may receive a reset signal appliedthrough a gate electrode connected to a reset line RST. The resettransistor TRRX is turned on when the reset signal is applied, to reseta voltage of the first node N1 as a voltage of the reset power sourceV_(RESET).

The amplification transistor TRAMP is connected between the reset powersource V_(RESET) and a signal line Vx, and a gate electrode of theamplification transistor TRAMP is connected to the first node N1. Theamplification transistor TRAMP operates as an amplifier that outputs asignal, corresponding to the voltage of the first node N1, to the signalline Vx.

In various embodiments, the structure of the sensor pixel SPXL is notlimited to that of the three transistors described above, and the sensorpixel SPXL may include, for example, four or more transistors or two orless transistors.

FIG. 4 illustrates an example of a path of light incident upon skin of auser's finger.

Referring to FIG. 4 , at least a portion of light irradiated onto skinof a person for the purpose of fingerprint sensing may be absorbed intothe skin.

Skin of a finger for fingerprint sensing includes an oily layer, anepidermis, and a dermis.

The oily layer, the epidermis, and the dermis have different lightabsorption rates and different refractive indices. Therefore, at least aportion of light irradiated onto the skin is diffused and refracted inthe oily layer, the epidermis, and the dermis, and then radiated to theoutside of the skin. That is, when light emitted from a light source orpixel is reflected by a user's finger, an incident angle of lightincident upon the finger and a resultant angle of light, such as of thelight reflected from the finger, are different from each other. Inaddition, the reflected light from the finger may be spread in multipledirections due to reflection, absorption, and refraction characteristicsof each of the oily layer, the epidermis, and the dermis.

The fingerprint detector 220 may use at least some of the photoelectricsensor pixels SPXL temporally disposed under a first color pattern CP1that are configured to substantially sense illuminance reflected by asensed fingerprint based on luminance of a second color pattern CP2 astemporally emitted by at least some of the display pixels PXL.

For example, when the finger is in contact with a fingerprint sensingarea including a non-emission area with a predetermined size, light of apredetermined pattern may be detected even in the non-emission area bylight which is passed into the skin and then redirected to the outsideof the skin.

A fake fingerprint may be one obtained by printing a fingerprint imageon a transparent film or paper, or may be generally made as afingerprint shape by putting a material such as silicon, rubber,gelatin, or glue for wood in a fingerprint mold and then hardening thematerial. Since the fake fingerprint has optical properties differentfrom those of the skin, the fake fingerprint may be detected asdisclosed herein based on such optical properties.

In particular, a two-dimensional (2D) fake fingerprint using a film, afake fingerprint manufactured by using a single material, and the likehave optical properties different from those of the finger, and hencedifferences exist in terms of light illuminance, light pattern, and thelike of reflected light detected. For example, a fingerprint detector,such as 220 shown in FIG. 1 , may detect a fake fingerprint by analyzinga difference between a degree of diffusion of light reflected from thefake fingerprint and a degree of diffusion of light reflected from theuser's finger.

FIG. 5A illustrates light detected from the fingerprint sensing area ofthe display panel of the display device shown in FIG. 1A.

Referring to FIGS. 1A and 5A, the fingerprint sensing area FSA may beincluded in the display area AA of the display panel 100.

In an embodiment, an indication image IMAGE_IND indicating thefingerprint sensing area FSA may be displayed in the fingerprint sensingarea FSA. The indication image IMAGE_IND may include afake-determination image pattern IPD for determination of a fakefingerprint. The indication image IMAGE_IND may be included in a userconvenience information which is an image for requesting a user to inputa fingerprint, and the user convenience information may include at leasta part (e.g., a color pattern, a planar shape) of the fake-determinationimage pattern IPD.

The fake-determination image pattern IPD may include a first colorpattern CP1 and a second color pattern CP2. A portion at which the firstcolor pattern CP1 is displayed may be defined as a low-luminance area ora non-emission area NEA, and a portion at which the second color patternCP2 is displayed may be defined as an emission area EA. For example,first and second color patterns CP1 and CP2 may be displayed adjacent toeach other at a scale smaller than that of a fingerprint.

Pixels PXL corresponding to the non-emission area NEA need not emitlight or may emit light having a luminance relatively lower than that ofthe emission area EA. When each pixel PXL includes sub-pixels emittinglights of different colors, a color in the emission area EA may bedifferent from that in the non-emission area NEA according to luminanceof the sub-pixels. For convenience of description, a case where thepixels PXL do not emit light in the non-emission area EA is described soas to clearly distinguish the emission area EA and the non-emission areaNEA from each other, without limitation thereto. Light may be emittedfrom pixels PXL corresponding to the emission area EA. The light emittedfrom the pixels PXL corresponding to the emission area EA may bereflected from a target object, such as but not limited to a realfingerprint or a fake fingerprint, and photoelectric sensors or sensorpixels SPXL may detect the light reflected from the fingerprint, forexample.

In an embodiment, the fake-determination image pattern IPD may include afirst sub-emission area or first emission area EA_S1, a firstsub-non-emission area or first non-emission area NEA_S1, and a secondsub-emission area or second emission area EA_S2, which are sequentiallyarranged along a first direction DR1. In some embodiments, thefake-determination image pattern IPD may further include a secondsub-non-emission or non-emission area NEA_S2 and a third sub-emission oremission area EA_S3, which are sequentially arranged along the firstdirection DR1 with respect to the second sub-emission area EA_S2. Thefirst sub-emission area EA_S1, the second sub-emission area EA_S2, andthe third sub-emission area EA_S3 may be included in the emission areaEA; and the first sub-non-emission area NEA_S1 and the secondsub-non-emission area NEA_S2 may be included in the non-emission areaNEA.

The first sub-emission area EA_S1, the second sub-emission area EA_S2,the third sub-emission area EA_S3, the first sub-non-emission areaNEA_S1, and the second sub-non-emission area NEA_S2 may extend in asecond direction DR2 intersecting the first direction DR1, withoutlimitation thereto. In FIG. 5A, the first sub-emission area EA_S1, thesecond sub-emission area EA_S2, and the third sub-emission area EA_S3are connected to each other through a reference emission area EA0, suchas an emission area at the outside of the fake-determination imagepattern IPD. The first sub-non-emission area NEA_S1 and the secondsub-non-emission area NEA_S2 are separated from each other along thefirst direction DR1. However, this is merely illustrative, and theemission area EA and the non-emission area NEA are not limited thereto.

Although described infra with reference to FIG. 7A, for example, thefirst sub-emission area EA_S1, the second sub-emission area EA_S2, andthe third sub-emission area EA_S3 may be separated from each other. Inanother example, the first sub-non-emission area NEA_S1 and the secondsub-non-emission area NEA_S2 may be connected to each other.

In some embodiments, widths or sizes of each of the firstsub-non-emission area NEA_S1 and the second sub-non-emission area NEA_S2in the first direction DR1 may be set such that a light illuminancesensed in each of the first sub-non-emission area NEA_S1 and the secondsub-non-emission area NEA_S2 is substantially maximized. Similarly, awidth of the second sub-emission area EA_S2 in the first direction DR1may be set such that a light illuminance sensed in the secondsub-emission area EA_S2 is substantially minimized. The width of each ofthe first sub-non-emission area NEA_S1 and the second sub-non-emissionarea NEA_S2 in the first direction DR1 and the width of the secondsub-emission area EA_S2 in the first direction DR1 may be describedinfra with reference to FIG. 8 .

An exemplary embodiment display device 1000 may include a display panel100 having pixels PXL configured to display a first image including userconvenience information and a fake-determination image pattern; aphotoelectric sensor SPXL, disposed on the display panel, and configuredto sense reflected light responsive to the fake-determination imagepattern and provide a sensing signal SS based on the reflected light;and a fingerprint detector 220 configured to determine whether a sensedfingerprint corresponding to the sensing signal is indicative of a fakefingerprint, based on the fake-determination image pattern and thesensing signal, where the user convenience information includes a firstcolor pattern, and where CP1 the fake-determination image patternincludes the first color pattern and a second color pattern CP2different from the first color pattern.

FIG. 5B illustrates sensed light amount or illuminance informationcorresponding to the portion I-I′ shown in FIG. 5A. FIG. 5C illustratesproperties of light reflected by a real fingerprint and a fakefingerprint, respectively, in response to the fake-determination imagepattern shown in FIG. 5A.

Referring to FIGS. 5A and 5B, a first graph C_REAL represents lightilluminance information of sensing image data such as a sensing signalSS responsive to a real fingerprint, and a second graph C_FAKErepresents light illuminance information of sensing image dataresponsive to a fake fingerprint. The x-axis of FIG. 5B represents pixelposition, and the y-axis represents light illuminance included in thesensing image data, where C_REAL and C_FAKE are each represented on asame relative scale with respect to the maximum light illuminance in thesensing image data.

As shown in FIG. 5B, in the first sub-non-emission area NEA_S1 and thesecond sub-non-emission area NEA_S2, a light illuminance, which is onaverage a first reference value or more, may be detected from the realfingerprint. This is because, as shown in FIG. 5C, light emitted fromthe first sub-emission area EA_S1 and the second sub-emission area EA_S2is refracted and diffused by a skin structure of the real fingerprint,and the diffused light is incident upon the first sub-non-emission areaNEA_S1.

Since light is diffused by the real fingerprint, a reflected luminancemay be relatively gently changed from the first sub-emission area EA_S1,such as in or including a boundary area between the emission area andthe non-emission area.

In the first sub-non-emission area NEA_S1 and the secondsub-non-emission area NEA_S2, light intensities, which are on averagesmaller than the first reference value, may be detected from the fakefingerprint. This is because, as shown in FIG. 5C, it is less likelythat reflected light will be diffused since a majority of lightreflected by the fake fingerprint using a film or the like is caused bysurface reflection.

Since light is hardly diffused by the fake fingerprint, the luminancemay be rapidly changed in the first sub-emission area EA_S1, such as inor including the boundary area between the emission area and thenon-emission area.

The fake fingerprint can be detected by analyzing a light illuminance inthe non-emission area NEA, a light illuminance in the emission area EA,and a difference between the light intensities due to a difference inoptical properties, such as a light absorptivity, a light reflexibility,a refractive index, a scattering rate, and/or the like, between the realfingerprint and the fake fingerprint.

FIGS. 6A and 6B illustrate an example of the fingerprint detectorincluded in the display device shown in FIG. 1A.

Referring to FIGS. 1A, 6A, and 6B, the fingerprint detector 220 mayinclude a pattern controller 225, a fake fingerprint detector 226, and afingerprint analyzer 227.

In an embodiment, the fingerprint detector 220 may further include amemory 228 and a use approval determiner 229.

The fingerprint detector 220 may perform fingerprint authenticationand/or fake fingerprint determination in response to a fingerprintsensing command CMD provided from the outside.

In an embodiment, the fingerprint detector 220 may further include ananalog-to-digital converter (ADC) 224 described with reference to FIG.3A. The ADC 224 may convert a sensing signal SS in an analog form intosensing data SD1, SD2, and SD3 in a digital form.

The pattern controller 225 may generate a fake-determination imagepattern IPD so as to perform fake fingerprint determination. Thefake-determination image pattern IPD may include a first color patternfor a non-emission area and a second color pattern for an emission area.The size, shape, number, and the like of the first color pattern for thenon-emission area included in the fake-determination image pattern IPDmay be randomly determined. Similarly, the size, shape, number, and thelike of the second color pattern for the emission area as included inthe fake-determination image pattern IPD may be randomly determined.Alternatively, the pattern controller 225 may randomly or otherwiseselect and output one of various image patterns stored in the memory228.

In an embodiment, the panel driver 210 may generate a data signalcorresponding to the fake-determination image pattern IPD and supply thegenerated data signal to the display panel 100.

The fake fingerprint detector 226 may receive first sensing data SD1corresponding to the second color pattern for the emission area of thefake-determination image pattern IPD and second sensing data SD2corresponding to the first color pattern for the non-emission area ofthe fake-determination image pattern IPD. The fake fingerprint detector226 may further receive, from the memory 228, light illuminanceinformation ALI set corresponding to the fake-determination imagepattern IPD. For example, light illuminance information ALI on each ofvarious fake-determination image patterns IPD may be recorded in thememory 228.

In an embodiment, the light illuminance information ALI may include afirst expected light pattern LP1 as an expected sensing lightilluminance of the second color pattern for the emission area of thefake-determination image pattern IPD, and a second expected lightpattern LP2 as an expected sensing light illuminance of the first colorpattern for the non-emission area of the fake-determination imagepattern IPD. The expectation sensing light illuminance may be a lightpattern or light illuminance to be detected from the fingerprintdetector 220 when a real fingerprint is sensed. For example, the lightilluminance information ALI may include information such as the lightpattern graph of the real fingerprint AF, which is shown in FIG. 5B.

In an embodiment, the light illuminance information ALI may be storedfor each fake-determination image pattern IPD when the display device1000 is initially set. In another embodiment, the light illuminanceinformation ALI may be optimized according to each fake-determinationimage pattern IPD through fingerprint analysis in fingerprintregistration of a user to be stored in the memory 228. In still anotherembodiment, the light illuminance information ALI may be updated in realtime according to the fake-determination image pattern IPD.

The fake fingerprint detector 226 may compare light profiles of thefirst expected light pattern LP1 and the first sensing data SD1, andcompare light profiles of the second expected light pattern LP2 and thesecond sensing data SD2. For example, a light profile may include alight illuminance pattern and/or a tendency of a light illuminance tochange at a corresponding portion of the fake-determination imagepattern IPD.

In an embodiment, the fake fingerprint detector 226 may calculate afirst accordance rate between the first sensing data SD1 and the firstexpected light pattern LP1 and a second accordance rate between thesecond sensing data SD2 and the second expected light pattern LP2. Aconfiguration for calculating the accordance rates may be implemented asa hardware configuration and/or a software configuration, such as butnot limited to a type used for data comparison, optical analysis, or thelike.

When each of the first accordance rate and the second accordance rate isa predetermined threshold value or more, the fake fingerprint detector226 may determine that a sensed fingerprint is a real fingerprint. Thethreshold value may be variably set according to sensing sensitivityand/or security level importance. For example, when each of the firstaccordance rate and the second accordance rate is about 90% or more, thefake fingerprint detector 226 may determine that the sensed fingerprintis a real fingerprint. However, this is merely illustrative, and thethreshold values of the first accordance rate and the second accordancerate may be set different from each other.

When at least one of the first accordance rate and the second accordancerate is less than the respective threshold value, the fake fingerprintdetector 226 may determine that the sensed fingerprint is a fakefingerprint.

When it is determined that the sensed fingerprint is a real fingerprint,the fake fingerprint detector 226 may output a first approval signalAS1. When it is determined that the sensed fingerprint is the fakefingerprint, the fake fingerprint detector 226 may output a firstrefusal signal RS1. The first approval signal AS1 or the first refusalsignal RS1 may be provided to the use approval determiner 229.

In an embodiment, the fake fingerprint detector 226 may generate anapproval weight AW, based on the first accordance rate and the secondaccordance rate. The probability that the sensed fingerprint will be areal fingerprint increases as the first and second accordance ratesincrease. For example, the approval weight AW may increase as the firstand second accordance rates increase. The approval weight AW may beprovided to the use approval determiner 229.

The fingerprint analyzer 227 may receive third sensing data SD3corresponding to the fingerprint sensing area FSA. Also, the fingerprintanalyzer 227 may receive registered fingerprint data RFD from the memory228. The fingerprint analyzer 227 may perform fingerprint authenticationby comparing the third sensing data SD3 with the registered fingerprintdata RFD.

In an embodiment, when the fake-determination image pattern IPD is notincluded in the fingerprint sensing area FSA, the third sensing data SD3may include sensing data about the entire fingerprint sensing area FSA.The third sensing data SD3 may be described in greater detail, infra,with reference to FIG. 9A.

Referring now to an embodiment shown in FIG. 6B, a fingerprint detector220_1 includes an ADC 224_1 outputting a third sensing signal SD3_1 to afingerprint analyzer 227_1, but the other elements are substantially thesame as the embodiment of FIG. 6A so duplicate description may beomitted. When the fake-determination image pattern IPD is included inthe fingerprint sensing area FSA, third sensing data SD3_1 from the ADC224_1 may include sensing data of a portion except an area correspondingto the first and second sensing data SD1 and SD2. The third sensing dataSD3_1 may be compared by the fingerprint analyzer 227_1 with the otherportion of the registered fingerprint data RFD except the non-emissionarea, and/or the fake-determination image pattern IPD, in the registeredfingerprint data RFD. The third sensing data SD3_1 may be described ingreater detail, infra, with reference to FIG. 9B.

Referring back to FIG. 6A, the fingerprint analyzer 227 may calculate athird accordance rate between the third sensing data SD3 and theregistered fingerprint data RFD. In an embodiment, the fingerprintanalyzer 227 may generate a fingerprint image corresponding to the thirdsensing data SD3, and perform fingerprint authentication by comparingthe fingerprint image with a fingerprint image of the registeredfingerprint data RFD. However, this is merely illustrative, and themethod for performing fingerprint authentication may be implemented byusing various fingerprint recognition methods as currently known orlater developed in the art. The fingerprint analyzer 227 may include ahardware configuration and/or a software configuration, used forfingerprint authentication.

When the third accordance rate is a predetermined threshold value ormore, the fingerprint analyzer 227 may determine that the sensedfingerprint accords with the registered fingerprint data RFD. When thethird accordance rate is less than the threshold value, the fingerprintanalyzer 227 may determine that the sensed fingerprint does not accordwith the registered fingerprint data.

When it is determined that the sensed fingerprint accords with theregistered fingerprint data RFD, the fingerprint analyzer 227 may outputa second approval signal AS2. When it is determined that the sensedfingerprint does not accord with the registered fingerprint data RFD,the fingerprint analyzer 227 may output a second refusal signal RS2. Thesecond approval signal AS2 or the second refusal signal RS2 may beprovided to the use approval determiner 229.

The use approval determiner 229 may finally determine whether use of thedisplay device 1000 is to be approved, based on the result of fakefingerprint determination and the result of fingerprint authentication,for example. In an embodiment, when the first approval signal AS1 andthe second approval signal AS2 are generated, the use approvaldeterminer 229 may output a use approval signal UAD to the panel driver210 and/or an external processor. Execution of the display device 1000or a corresponding application may be approved based on the use approvalsignal UAD.

In an embodiment, when at least one of the first refusal signal RS1 andthe second refusal signal RS2 is generated, the use approval determiner229 may output a use disapproval signal UDAD to the panel driver 210and/or the external processor. The display device 1000 is not approvedfor the requested use and/or the corresponding application is notexecuted based on the use disapproval signal UDAD.

In an embodiment, the fake fingerprint detector 226 may generate theapproval weight AW instead of the first approval signal AS1 and thefirst refusal signal RS1. The use approval determiner 229 receiving theapproval weight AW and the second approval signal AS2 may determine useapproval according to a magnitude of the approval weight AW. When theuse approval determiner 229 receives the second refusal signal RS2, theuse approval determiner 229 may output the use disapproval signal UDAD,regardless of the size of the approval weight AW.

As described above, the display device 1000 in accordance withembodiments of the present disclosure can detect a fake fingerprint byanalyzing a light illuminance or light pattern in the first colorpattern for a non-emission area included in the fake-determination imagepattern IPD. Accordingly, the accuracy and reliability of fingerprintdetection can be high without adversely impacting manufacturing costand/or configuration.

FIG. 7A illustrates an example of an image displayed on the displaypanel of the display device shown in FIG. 1A. FIG. 7B illustratesvarious examples of a fake-determination image pattern included in theimage shown in FIG. 7A.

Referring to FIGS. 1A, 5A, and 7A, an image including user convenienceinformation may be displayed. In an embodiment, the image including theuser convenience information is an image for requesting a user to inputa fingerprint, and may include an indication image IMAGE_IND indicatingthe fingerprint sensing area FSA.

As shown in FIG. 7A, the indication image IMAGE_IND may include afingerprint pattern configured to detect forging or imitating of afingerprint. For example, a portion representing a ridge of thefingerprint may be expressed as an emission area, and a portionrepresenting a valley of the fingerprint may be expressed as anon-emission area.

The indication image IMAGE_IND may include a first color pattern CP1 ofthe fake-determination image pattern IPD of FIG. 5A. For example, in anarea AA corresponding to the fake-determination image pattern IPD, suchan image pattern in which a sub-emission area and a sub-non-emissionarea are alternately disposed as described, supra, with reference toFIG. 5A, the indication image IMAGE_IND may include the first colorpattern CP1. The first color pattern CP1 may have a low luminance,and/or the other portion of the indication image IMAGE_IND except thefirst color pattern CP1 may be displayed as substantially black.Therefore, the indication image IMAGE_IND including the first colorpattern CP1 may be viewed by a user and/or indicate the fingerprintsensing area FSA according to a relative luminance difference or arelative color difference.

The first color pattern CP1 of the fake-determination image pattern IPDmay be displayed while being included in the indication image IMAGE_IND,and therefore, it may be less likely that the fake-determination imagepattern IPD will be exposed or be independently identified by a user.

In some embodiments, fake-determination image patterns FDIP1 to FDIP9may include non-emission areas NEA1 to NEA6, for displaying first colorpatterns, having various shapes and various sizes.

Referring to FIG. 7B, the non-emission areas NEA1 to NEA6, fordisplaying first color patterns, included in the fake-determinationimage patterns FDIP1 to FDIP9, respectively, may have a polygonal shapesuch as quadrangular shape, and/or a free shape such as a circular shapeor an elliptical shape. In addition, a plurality of non-emission areasNEA51 and NEA52 for displaying first color patterns may be included asshown in a fifth fake-determination image pattern FDIP5. Moreover, aplurality of emission areas for displaying second color patterns,surrounding a non-emission area NEA3 for displaying a first colorpattern, may be included as shown in a third fake-determination imagepattern FDIP3.

In an embodiment, the fake-determination image patterns FDIP1 to FDIP9may have the same size as the fingerprint sensing area FSA. In anotherembodiment, the fake-determination image patterns FDIP1 to FDIP9 mayoverlap with a portion of the fingerprint sensing area FSA.

In an embodiment, the pattern controller 225 may randomly or selectivelychange the fake-determination image pattern IPD shown in FIGS. 6A and 6Bto be displayed on the display panel 100 during a predetermined period.For example, the pattern controller 225 may change thefake-determination image pattern IPD whenever the fake fingerprintdetermination is performed. For example, one of the first to ninthfake-determination image patterns FDIP1 to FDIP9 may be randomlyselected whenever the fake fingerprint determination is performed.

Accordingly, the first expected light pattern LP1 and the secondexpected light pattern LP2 may be randomly changed whenever the fakefingerprint determination is performed. Thus, a fake attempt using animage or surface material having optical properties similar to those ofskin can be blocked, and the reliability of fingerprint detection can beoptimized.

FIG. 8 illustrates a size of the first color pattern included in thefake-determination image pattern shown in FIG. 7B.

Referring to FIGS. 5A, 7B, and 8 , a size of a non-emission area NEAcorresponding to the first color pattern CP1 of the fake-determinationimage pattern IPD may be defined as a shortest distance between emissionareas, or second color patterns, adjacent to the non-emission area NEA,such as a width W1 or W2 of the non-emission area NEA. In other words,the size of the non-emission area NEA may be defined as a distancebetween the emission areas adjacent to the non-emission area NEA on areference line penetrating the area center of the non-emission area NEA,for example.

In some embodiments, a width of the non-emission area of thefake-determination image pattern IPD may be set such that a lightilluminance sensed in the non-emission area NEA with respect to a realfingerprint is substantially maximized.

As shown in FIG. 8 , a first real graph C_REAL1 and a second real graphC_REAL2 represent light illuminance information of a sensing signalaccording to a real fingerprint. The first real graph C_REAL1 representslight illuminance information associated with an emission area EA, suchas light emitted and diffused from the emission area EA, that is locatedat one side of the non-emission area NEA in the fake-determination imagepattern IPD, and the second real graph C_REAL2 represents lightilluminance information associated with an emission area EA, such aslight emitted and diffused from the emission area EA, that is located atthe other side of the non-emission area NEA in the fake-determinationimage pattern IPD.

Similarly, a first fake graph C_FAKE1 and a second fake graph C_FAKE2represent light illuminance information of a sensing signal according toa fake fingerprint. The first fake graph C_FAKE1 represents lightilluminance information associated with an emission area EA located atone side of the non-emission area NEA in the fake-determination imagepattern IPD, and the second fake graph C_FAKE2 represents lightilluminance information associated with an emission area EA located atthe other side of the non-emission area NEA in the fake-determinationimage pattern IPD.

Each of the first real graph C_REAL1 and the second real graph C_REAL2is relatively gently changed at a boundary portion between the emissionarea and the non-emission area, and each of the first fake graph C_FAKE1and the second fake graph C_FAKE2 is relatively rapidly changed at aboundary portion between the emission area and the non-emission area. Ata first point P1 spaced apart from the emission area by a specificdistance, a light illuminance difference between the first real graphC_REAL1 and the first fake graph C_FAKE1 may have a maximum value MAX.Similarly, at a second point P2 spaced apart from the emission area by aspecific distance, a light illuminance difference between the secondreal graph C_REAL2 and the second fake graph C_FAKE2 may have a maximumvalue MAX.

Although the same maximum value MAX is shown at both points P1 and P2,it shall be understood that a first MAX1 may occur at P1, and a secondMAX2 may occur at P2, where MAX1 and MAX2 may be different.

When the non-emission area NEA has a relatively large first width W1,the first point P1 and the second point P2 are located to be spacedrelatively far apart from each other. Accordingly, a light illuminancedifference between the real graphs C_REAL1 and C_REAL2 and the fakegraphs C_FAKE1 and C_FAKE2 may be expressed as two substantiallynon-overlapping parabolas having a maximum value K, where K is apositive number.

When the non-emission area NEA has a second width W2 sufficientlysmaller than the first width W1, the first point P1 and the second pointP2 substantially overlap with each other. Accordingly, when P1 and P2substantially overlap with each other, the light illuminance differencebetween the real graphs C_REAL1 and C_REAL2 and the fake graphs C_FAKE1and C_FAKE2 may be expressed as one parabola having a value of maximum2K. Since the difference between the light illuminance according to thereal fingerprint and the light illuminance according to the fakefingerprint is large, the real fingerprint and the fake fingerprint canbe more easily distinguished from each other. That is, the fakefingerprint can be more easily detected. When considering that light ishardly detected with respect to the fake fingerprint in the non-emissionarea NEA, the light illuminance sensed in the non-emission area NEA withrespect to the real fingerprint may become largest. In other words, thesecond width W2 of the non-emission area NEA may be set such that thelight illuminance K_max sensed in the non-emission area NEA issubstantially maximized.

When the non-emission area NEA has a third width W3 smaller than thesecond width W2, the first point P1 and the second point P2 do notoverlap with each other, and the light illuminance difference betweenthe real graphs C_REAL1 and C_REAL2 and the fake graphs C_FAKE1 andC_FAKE2 may be expressed as a curve having values relatively close to K.

As described with reference to FIG. 8 , the width of the first colorpattern CP1 of the fake-determination image pattern IPD, or thenon-emission area NEA corresponding to the first color pattern CP1, maybe set such that the light illuminance sensed in the non-emission areaNEA with respect to the real fingerprint is substantially maximized. Alarge difference between the light illuminance according to the realfingerprint and the light illuminance according to the fake fingerprintis represented, and the fake fingerprint can be detected on this basis,as compared with the real fingerprint.

As shown in FIG. 5A, when the fake-determination image pattern IPDincludes an emission area EA, such as the second sub-emission area EA_S2located between the first sub-non-emission area NEA_S1 and the secondsub-non-emission area NEA_S2, a width of the emission area EA may be setsuch that a light illuminance sensed in the emission area EA issubstantially minimized. For example, the width of the emission area EAmay be greater than or equal to the second width W2 of the non-emissionarea NEA.

FIGS. 9A to 9D illustrate timing for an operation of the display deviceshown in FIG. 1A. In FIGS. 9A to 9D, an operation of the display device1000 in a first mode is illustrated, and the display device 1000 maydisplay a general image having a first refresh rate in the first mode.

Referring to FIGS. 1A, 3A, and 9A, before a first time t1, the displaydevice 1000 may be in a sleep state or a power-off state. Before t1, anyimage, such as but not limited to any user interface UI image, need notbe displayed on the display panel 100.

At the first time t1, a wake-up signal may be provided to the displaydevice 1000 from the outside. For example, the wake-up signal may begenerated by a touch input, a key input, or the like to the displaydevice 1000, and be provided to the controller 223 and/or externalapplication processor AR In addition, a signal corresponding to thewake-up signal may be provided to the horizontal driver 221 and thevertical driver 222. The horizontal driver 221, the vertical driver 222,and the controller 223, such as in the fingerprint detector 220, mayperform a wake-up operation or starting operation in response to thewake-up signal.

At the first time t1, the pattern controller 225 described withreference to FIGS. 6A and 6B may generate a first color pattern CP1 of afake-determination image pattern IPD, and the panel driver 210 maygenerate a data signal corresponding to an indication image and/or imageincluding user convenience information, including the first colorpattern CP1, and supply the generated data signal to the display panel100. Therefore, the display panel 100 may display the indication imageIMAGE_IND described with reference to FIG. 7A. For example, as shown inFIG. 9A, the first color pattern CP1 or the indication image includingthe same may have a planar shape of an iconic fingerprint, which may beobtained by imitating a fingerprint.

Subsequently, at a second time t2, the wake-up operation of thehorizontal driver 221, the vertical driver 222, and the controller 223may be completed, and the controller 223 may operate the photoelectricsensor PS. The photoelectric sensor PS may perform an initializationoperation until before a touch input for fingerprint input occurs.

At a third time t3, the touch input for fingerprint input may occur.

In an embodiment, the display panel 100 may allow light to beadditionally emitted in an emission area except the fake-determinationimage pattern IPD in the fingerprint sensing area in response to thetouch input, such as by activating a Light ON signal. Accordingly, lightmay be additionally emitted in an area corresponding to a second colorpattern CP2 of the fake-determination image pattern IPD, and the entirefingerprint sensing area may emit light with a high luminance.

In an embodiment, a touch coordinate with respect to a touch position atwhich the touch input occurs may be provided to the horizontal driver221, and the horizontal driver 221 may operate the photoelectric sensorPS, corresponding to the touch coordinate.

In a period between the third time t3 and a fourth time t4, thephotoelectric sensor PS may generate a first sensing signal for fakefingerprint determination. The first sensing signal may correspond tothe first sensing data SD1 and the second sensing data SD2, which aredescribed with reference to FIGS. 6A and 6B.

In a period from before and/or after the fourth time t4, to a fifth timet5, the vertical driver 222 may transmit the first sensing signalprovided from the photoelectric sensor PS to the controller 223.

In a period between the fourth time t4 and the fifth time t5, thephotoelectric sensor PS may perform an initialization operation.

In addition, at the fourth time t4, the display panel 100 may allowlight to be emitted in the entire fingerprint sensing area in responseto the first sensing signal. For example, the display panel 100 maysuspend the display of the indication image including thefake-determination image pattern IPD, and allow the entire fingerprintsensing area to emit light.

That is, the pattern controller 225 described with reference to FIG. 6Amay generate the fake-determination image pattern IPD in a first periodbetween the first time t1 and the fourth time t4, and suspend thegeneration of the fake-determination image pattern IPD in a secondperiod between the fourth time t4 and a sixth time t6.

Each of the first period and the second period may include at least oneframe period. In addition, the second period may proceed after the firstperiod is completed, although the present disclosure is not limitedthereto as the periods may also proceed in parallel, or the secondperiod may precede the first period. A fingerprint detection proceduremay be performed throughout the first period and the second period, anda target object may continuously touch the fingerprint sensing area FSAfor a time including at least the first period and the second period.However, this is merely illustrative, and the order, intervals, lengths,and the like of the first period and the second period are not limitedthereto.

At the fifth time t5, the controller 223 may generate sensing datathrough image processing on the first sensing signal. The controller 223may also compare the sensing data with predetermined light illuminanceinformation, corresponding to the fake-determination image pattern, andperform fake fingerprint determination, through the fake fingerprintdetector 226 described with reference to FIG. 6A, supra.

In an embodiment, when it is determined that a sensed fingerprint is afake fingerprint, the controller 223 may output a first refusal signalRS1 representing an instance where matching between the sensing data andthe light illuminance information has failed, such as a matching fail.

In an embodiment, when it is determined that the sensed fingerprint is areal fingerprint, the controller 223 may output a first approval signalAS1 associated with unlock of a corresponding application.

In a period between the fifth time t5 and the sixth time t6, thephotoelectric sensor PS may generate a second sensing signal forfingerprint authentication. The second sensing signal may correspond tothe third sensing data SD3 described with reference to FIG. 6A.

Before and/or after the sixth time t6, the vertical driver 222 maytransmit the second sensing signal provided from the photoelectricsensor PS to the controller 223, and the controller 223 may generatesensing data about the second sensing signal and perform fingerprintauthentication by comparing the sensing data with registered fingerprintdata through the fingerprint analyzer 227 or 227_1, such as describedwith reference to FIGS. 6A and 6B, respectively. Since the sensing datais acquired by using the total light information which the photoelectricsensor PS receives, the accuracy and reliability of fingerprintauthentication can be optimized.

Although it has been described that the display panel 100 allows lightto be emitted in the entire fingerprint sensing area in response to thetransmission of the first sensing signal at the fourth time t4, thepresent disclosure is not limited thereto.

As shown in FIG. 9B, like the period between the third time t3 and thefourth time t4, the display panel 100 may additionally display an imageincluding the fake-determination image pattern IPD at the fourth timet4. In the period between the fifth time t5 and the sixth time t6, thephotoelectric sensor PS may generate a second sensing signal forfingerprint authentication, and the second sensing signal may correspondto the third sensing data SD3_1 described with reference to FIG. 6B.

Although it has been described that, at the third time t3, the firstcolor pattern CP1 is maintained, and light is additionally emitted in anarea corresponding to the second color pattern CP2, the presentdisclosure is not limited thereto.

An embodiment modifying FIG. 9A is illustrated in FIG. 9C, and anembodiment modifying FIG. 9B is illustrated in FIG. 9D. Duplicatedescription may be omitted.

As shown in FIGS. 9C and 9D, a luminance and/or a color of a first colorpattern CP1_1 and CP1_2 may be changed from CP1_1 to CP1_2 at the thirdtime t3. For example, a first color pattern CP1_1 having a relativelyhigh luminance, such as the first color pattern CP1_1 corresponding towhite, may be displayed until the third time t3, and a first colorpattern CP1_2 having a relatively lower luminance, such as the firstcolor pattern CP1_2 corresponding to black, may be displayed after thethird time t3. That is, a planar shape of the first color pattern CP1_1and CP1_2, and/or a planar shape of an indication image including thesame, is not changed, and the luminance and/or the color of the firstcolor pattern CP1_1 and CP1_2 may be changed with respect to before andafter the third time t3. For example, the first and second colorpatterns CP1 and CP2 may be concurrently displayed by the display pixelsPXL and sensed by the photoelectric sensor pixels SPXL.

Since light is additionally emitted in an area corresponding to thesecond color pattern CP2 at the third time t3, the luminance and/or thecolor of the fake-determination image pattern including the first colorpattern CP1_1 and CP1_2 and the second color pattern CP2 may be reversedwith respect to the third time t3. That is, in an embodiment, a firstcolor pattern having a relatively lower luminance, such as onecorresponding to black, may be displayed before the third time t3, and afirst color pattern having a relatively high luminance, such as onecorresponding to white, may be displayed after the third time t3.

As described with reference to FIGS. 9A to 9D, the display device 1000may detect a fake fingerprint by using the fake-determination imagepattern IPD displayed in the first period, and perform fingerprintauthentication by using sensing data sensed in the second period. Thus,the reliability of the fake fingerprint detection and the fingerprintauthentication can be optimized.

The display device 1000 may also display an indication image includingthe first color pattern of the fake-determination image pattern IPDthrough the display panel 100, before a touch input to the fingerprintsensing area FSA for fingerprint input occurs. That is, thefake-determination image pattern IPD is substantially displayed beforethe touch input occurs in addition to after the touch input occurs, sothat the time at which the fake-determination image pattern IPD isdisplayed can be set freely. Further, since the first color pattern CP1of the fake-determination image pattern IPD is included in theindication image, the fake-determination image pattern IPD can beprevented from being independently identified by a user or being exposedto the user, even when a state is maintained in which thefake-determination image pattern IPD is displayed before the touch inputoccurs.

Although an exemplary embodiment has been described with respect toFIGS. 9A to 9D where the indication image including thefake-determination image pattern is displayed on the display panel 100when a wake-up signal based on the touch input, the key input, or thelike to the display device 1000 is provided, the present disclosure isnot limited thereto.

FIGS. 10A and 10B illustrate an operation of the display device shown inFIG. 1A. In FIGS. 10A and 10B, an operation of the display device 1000in a second mode is illustrated, and the display device 1000 may displaya power-saving image having a second refresh rate slower than the firstrefresh rate in the second mode. For example, the second mode may be analways on display (AOD) mode in which the display device 1000 displays apartially limited image in a sleep state.

In the sleep state, the display device 1000 may display the indicationimage IMAGE_IND described with reference to FIG. 7A, such as theindication image including the first color pattern of thefake-determination image pattern IPD.

As shown in FIG. 10A, when a touch input for fingerprint input occurs,the display panel 100 may allow light to be additionally emitted in anemission area except for the first color pattern CP1 shown in FIGS. 9Aand 9B of the fake-determination image pattern IPD in the fingerprintsensing area, in response to the touch input. Alternatively, as shown inFIG. 10B, when a touch input for fingerprint input occurs, the displaypanel 100 may allow the fake-determination image pattern IPD to bereversed in the fingerprint sensing area, in response to the touchinput.

That is, the display device 1000 may perform an operation after thethird time t3 described with reference to FIGS. 9A to 9D. Acorresponding application may be unlocked based on both a qualifyingfake fingerprint determination result and a qualifying fingerprintauthentication result.

As described with reference to FIGS. 10A and 10B, the indication imageincluding the first color pattern of the fake-determination imagepattern IPD may be displayed on the display panel 100, even before thewake-up signal is provided to the display device 1000.

FIG. 11 illustrates a method for driving the display device inaccordance with embodiments of the present disclosure.

Hereinafter, in FIGS. 11 to 16 , components substantially similar tothose described above may be designated by like reference numerals, andoverlapping descriptions of the components may be omitted.

Referring to FIGS. 1A to 11 , in the method for driving the displaydevice, a fake-determination image pattern IPD including an emissionarea EA and a non-emission area NEA may be displayed in the fingerprintsensing area FSA at function block S100, sensing data corresponding tothe fingerprint sensing area FSA may be generated by using thephotoelectric sensor PS at function block S200, a fake fingerprint maybe determined by comparing light illuminance information ALIcorresponding to the fake-determination image pattern IPD with thesensing data at function block S300, fingerprint authentication may beperformed by comparing the sensing data with registered fingerprint dataRFD at function block S400, and use approval may be determined based ona fingerprint authentication result and a fake fingerprint determinationresult at function block S500.

A detailed operation of the method including the fingerprintauthentication and the fake fingerprint determination may be performedby using various methods as shown in FIGS. 12 to 16 .

An exemplary embodiment method of FIG. 11 for driving the display device1000 of FIG. 1 includes displaying a first image including userconvenience information through a display panel at block S100;generating sensing data corresponding to a fingerprint sensing area byusing a photoelectric sensor at block S200; and determining whether asensed fingerprint corresponding to the sensing data is a fakefingerprint by comparing expected sensing light illuminance informationbased on the first image with sensed light illuminance information ofthe sensing data at block S300, where the first image includes a firstcolor pattern CP1 in the fingerprint sensing area FSA of the displaypanel 100, and the fake-determination image pattern includes the firstcolor pattern and a second color pattern CP2 different from the firstcolor pattern.

FIG. 12 illustrates an example of the method shown in FIG. 11 .

Referring to FIGS. 1A, 3A, 9A to 9D, and 11 , the display panel 100 maybe powered on at function block S110 or perform a wake-up operation inresponse to a wake-up signal generated by a touch input, a key input, orthe like to the display device 1000.

Subsequently, in a first period, a first color pattern CP1 of afake-determination image pattern IPD may be displayed on the displaypanel 100 at function block S120. A non-limiting example will bedescribed with reference to FIG. 9A. The first period may be a periodbetween the first time t1 and the fourth time t4.

A touch input may be sensed in the fingerprint sensing area FSA atfunction block S125, and a first sensing signal for fingerprintdetermination may be generated by the photoelectric sensor PS inresponse to the touch input. Fake fingerprint determination may beperformed based on the first sensing signal in the controller 223 and/orapplication processor.

In a second period such as after the fourth time t4, the display of thefake-determination image pattern IPD on the display panel 100 may besuspended, and an image for fingerprint sensing may be displayed atfunction block S130. A non-limiting example will be described withreference to FIG. 9A. The second period may be a period between thefourth time t4 and the sixth time t6. However, the present disclosure isnot limited thereto. A non-limiting example will be described withreference to FIG. 9B. The image for fingerprint sensing may include thefake-determination image pattern IPD.

As described with reference to FIG. 9A, the display panel 1000 may allowthe entire fingerprint sensing area to emit light. A second sensingsignal for fingerprint authentication may be generated by thephotoelectric sensor PS, and fingerprint authentication may be performedbased on the second sensing signal in the controller 223 and/orapplication processor.

FIG. 13 illustrates an example of the method shown in FIG. 11 .

Referring to FIGS. 1A to 13 , a fake fingerprint determination procedureand a fingerprint authentication procedure may be sequentially performedby using light sensed from the fingerprint sensing area FSA including afake-determination image pattern IPD.

At function block S200 of FIG. 11 , first to third sensing data SD1,SD2, and SD3 may be generated based on the light sensed from thefingerprint sensing area FSA including the fake-determination imagepattern IPD.

At function block S300 of FIG. 11 , determining the fake fingerprint mayinclude calculating a first accordance rate by comparing a firstexpected light pattern LP1 of an emission area EA, which is included inlight illuminance information ALI, with the first sensing data SD1, andcalculating a second accordance rate by comparing a second expectedlight pattern LP2 included in the light illuminance information ALI withthe second sensing data SD2 at function block S320 of FIG. 13 .

The first accordance rate may be compared with a first threshold value,and the second accordance rate may be compared with a second thresholdvalue at decision block S340 of FIG. 13 .

When the first accordance rate is less than the first threshold valueand when the second accordance rate is less than the second thresholdvalue, it may be determined that a sensed fingerprint is a fakefingerprint. In addition, when the first accordance rate is less thanthe first threshold value or when the second accordance rate is lessthan the second threshold value, it may be determined that the sensedfingerprint is a fake or unauthorized fingerprint. When it is determinedthat the sensed fingerprint is a fake fingerprint or an unauthorizedfingerprint, the use of the display device 1000 or a correspondingapplication may be disapproved at function block S540. In addition, whenit is determined that the sensed fingerprint is a fake fingerprint, thefunction block S400 of FIG. 11 , for performing the fingerprintauthentication, may be omitted.

When the first accordance rate is the first threshold value or more andwhen the second accordance rate is the second threshold value or more,it may be determined that the sensed fingerprint is a real fingerprint.In addition, when the first accordance rate is the first threshold valueor more and when the second accordance rate is the second thresholdvalue or more, the function block S400 for performing the fingerprintauthentication, which is shown in FIG. 11 , may be executed.

For example, the function block S400 of FIG. 11 for performing thefingerprint authentication may include calculating a third accordancerate as an accordance rate between third sensing data SD3 and registeredfingerprint data RFD at function block S420 of FIG. 13 , and comparingthe third accordance rate with a third threshold value at function blockS440 of FIG. 13 .

When the third accordance rate is less than the third threshold value,it may be determined that the sensed fingerprint does not accord withthe registered fingerprint data RFD. For example, when it is determinedthat the sensed fingerprint does not accord with the registeredfingerprint data RFD, the use of the display device 1000 or thecorresponding application may be disapproved at function block S540 ofFIG. 13 .

When the third accordance rate is the third threshold value or more, itmay be determined that the sensed fingerprint accords with theregistered fingerprint data RFD. For example, when it is determined thatthe sensed fingerprint accords with the registered fingerprint data RFD,the use of the display device 1000 or the corresponding application maybe approved at function block S520 of FIG. 13 .

That is, when it is determined that the third sensing data SD3 and theregistered fingerprint data RFD accord with each other, and the sensedfingerprint is a real fingerprint, the use of the display device 1000 orthe corresponding application may be approved at function block S520 ofFIG. 13 .

As described above, in the method in accordance with the embodimentshown in FIG. 13 , the fingerprint authentication is performed after itis determined whether or not the sensed fingerprint is a fakefingerprint, such that the calculation load in fingerprint detectionand/or authentication can be decreased.

FIG. 14 illustrates an example of the method shown in FIG. 11 .

Referring to FIGS. 1A to 11 and 14 , a fake fingerprint determinationprocedure and a fingerprint authentication procedure may be performed inparallel by using light sensed from the fingerprint sensing area FSAincluding a fake-determination image pattern IPD.

The function block S300 of FIG. 11 for determining the fake fingerprintmay include calculating first and second accordance rates at functionblock S320 of FIG. 14 , and calculating an approval weight AW, based onthe first accordance rate and the second accordance rate at functionblock S350 of FIG. 14 .

In an embodiment, the function block S400 of FIG. 11 for performing thefingerprint authentication may be performed in parallel to the functionblock S300 of FIG. 11 for determining the fake fingerprint. The functionblock S400 of FIG. 11 for performing the fingerprint authentication mayinclude calculating a third accordance rate at function block S420 ofFIG. 14 , and comparing the third accordance rate and a third thresholdvalue at decision block S440 of FIG. 14 .

When the third accordance rate is less than the third threshold value,the use of the display device 1000 or a corresponding application may bedisapproved at function block S540 of FIG. 14 .

When a third accordance rate is the third threshold value or more, thefunction block S500 of FIG. 11 for determining the use approval may beperformed. The approval weight AW and a predetermined use approvalreference may be compared at decision block S510 of FIG. 14 .

When the approval weight AW is the use approval reference or more, theuse of the display device 1000 or the corresponding application may beapproved at function block S520 of FIG. 14 .

When the approval weight AW is less than the use approval reference, theuse of the display device 1000 or the corresponding application may bedisapproved at function block S540 of FIG. 14 .

As described above, an image is acquired once by reflected light in thefingerprint sensing area FSA including the fake-determination imagepattern IPD, so that the fake fingerprint detection and the fingerprintauthentication can be performed in parallel. Thus, the time required toperform fingerprint detection and use approval can be minimized.

FIG. 15 illustrates an example of the method shown in FIG. 11 .

In FIG. 15 , components substantially similar to those described withreference to FIGS. 11 and 13 may be designated by like referencenumerals, and overlapping descriptions of such components may beomitted.

Referring to FIGS. 1A to 13 and 15 , the function block S300 of FIG. 11for determining the fake fingerprint may be performed based on afake-determination image pattern IPD in a first period, and the functionblock S400 of FIG. 11 for performing the fingerprint authentication maybe performed based on an image for fingerprint sensing in a secondperiod.

In the first period, a first color pattern CP1 of the fake-determinationimage pattern IPD may be displayed in the fingerprint sensing area FSAat function block S120 of FIG. 15 . First and second sensing data SD1and SD2 may be calculated based on the fake-determination image patternIPD at function block S220, and first accordance rate and a secondaccordance rate may be calculated at function block S320.

Then, the first accordance rate and a first threshold value may becompared, and the second accordance rate and a second threshold valuemay be compared at decision block S340.

When the first accordance rate is less than the first threshold value orwhen the second accordance rate is less than the second threshold value,the use of the display device 1000 or a corresponding application may bedisapproved at function block S540.

When the first accordance rate is the first threshold value or more andwhen the second accordance rate is the second threshold value or more,the second period may proceed. In the second period, an image forfingerprint sensing may be displayed in the fingerprint sensing area FSAat function block S130 of FIG. 15 . For example, the entire fingerprintsensing area FSA may emit light with a high luminance in the secondperiod.

Third sensing data SD3 about the entire fingerprint sensing area FSA maybe calculated at function block S230, and a third accordance ratebetween the third sensing data SD3 and registered fingerprint data RFDmay be calculated at function block S430.

The third accordance rate and a third threshold value may be compared atdecision block S450. If the third accordance rate is less than the thirdthreshold value, the use of the display device 1000 and thecorresponding application may be disapproved at function block S540.When the third accordance rate is the third threshold value or more, theuse of the display device 1000 and the corresponding application may beapproved at function block S520.

In the embodiment shown in FIG. 15 , the reliability of fake fingerprintdetection and the reliability of fingerprint authentication can befurther optimized, as compared with the method shown in FIG. 13 .

FIG. 16 illustrates an example of the method shown in FIG. 11 .

In FIG. 16 , components substantially similar to those described withreference to FIGS. 11, 14 and/or 15 may be designated by like referencenumerals, and overlapping descriptions of such components may beomitted.

Referring to FIGS. 1A to 16 , the function block S300 of FIG. 11 fordetermining a fake fingerprint, based on a fake-determination imagepattern IPD, may be performed in a first period, and the function blockS400 of FIG. 11 for performing the fingerprint authentication, based ona general image, may be performed in a second period P2.

In an embodiment, an approval weight AW may be calculated based on afirst accordance rate and a second accordance rate at function blockS350 of FIG. 16 . In addition, fingerprint authentication, such asincluding function blocks S130, S230, S430, and decision block S450 ofFIG. 16 , based on third sensing data SD3, may be performed in a secondperiod, regardless of the result of the approval weight AW.

The approval weight AW and a use approval reference may be compared atdecision block S515.

If a third accordance rate is a third threshold value or more and whenthe approval weight AW is the use approval reference or more, the use ofthe display device 1000 or a corresponding application may be approvedat function block S520. If the third accordance rate is less than thethird threshold value or if the approval weight AW is less than the useapproval reference, the use of the display device 1000 or thecorresponding application may be disapproved at function block S540.

In the embodiment shown in FIG. 16 , the accuracy of fake fingerprintdetermination may be optimized.

As described above, in the display device and the method for driving thesame in accordance with the embodiments of the present disclosure, afake fingerprint can be detected by analyzing a light illuminance orlight pattern in the non-emission area included in a fake-determinationimage pattern. Accordingly, the accuracy and reliability of fingerprintdetection can be optimized without adversely impacting manufacturingcost and/or configuration.

Exemplary embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense and not for purposes of limitation. In someinstances, as would be apparent to one of ordinary skill in thepertinent art as of the filing or priority date of the presentapplication, features, characteristics, and/or elements described inconnection with a particular embodiment may be used singly or incombination with features, characteristics, and/or elements described inconnection with other embodiments unless otherwise specificallyindicated. Accordingly, it will be understood by those of ordinary skillin the pertinent art that various changes in form and details may bemade without departing from the scope and sprit of the presentdisclosure as set forth in the following claims.

1-32. (canceled)
 33. A display device comprising: a display panelincluding a plurality of pixels, the display panel displaying a firstimage including user convenience information; a photo sensor disposed onone surface of the display panel and configured to sense light; and afingerprint detector configured to determine whether a sensedfingerprint corresponding to a sensing signal supplied from the photosensor is a fake fingerprint, based on the sensing signal, wherein thefirst image includes the fake-determination image pattern in afingerprint sensing area of the display panel, and thefake-determination image pattern includes a first pattern having a firstplanar shape.
 34. The display device of claim 33, wherein the userconvenience information includes an indication image indicating thefingerprint sensing area, and wherein the indication image incudes thefake-determination image pattern.
 35. The display device of claim 34,wherein, when a touch input occurs in the fingerprint sensing area, acolor or luminance of the fake-determination image pattern is reversed,and the first planar shape of the first pattern is not changed.
 36. Thedisplay device of claim 35, wherein the fingerprint detector determineswhether the sensed fingerprint is a fake fingerprint by analyzing alight illuminance sensed in a first area in which the first pattern isdisplayed.
 37. The display device of claim 36, wherein if the lightilluminance sensed in the first area is smaller than a predeterminedfirst reference light illuminance, the fingerprint detector determinesthat the sensed fingerprint is a fake fingerprint.
 38. The displaydevice of claim 36, wherein, when a light illuminance sensed in a secondarea in which the first pattern is not displayed is greater than apredetermined second reference light illuminance, the fingerprintdetector determines that the sensed fingerprint is a fake fingerprint.39. The display device of claim 33, wherein the first image includes afingerprint pattern imitating a fingerprint, and wherein the fingerprintpattern includes the first pattern.
 40. The display device of claim 33,wherein the fingerprint detector controls the fake-determination imagepattern of the fingerprint sensing area of the display panel, which isused for fingerprint sensing, and performs fingerprint authentication onthe sensed fingerprint, based on the sensing signal.
 41. The displaydevice of claim 40, wherein the fingerprint detector includes: a patterncontroller configured to generate the fake-determination image patternsuch that the first pattern is included in the fingerprint sensing area;a fake fingerprint detector configured to perform fake fingerprintdetermination by comparing first sensing data corresponding to the firstpattern of the fake-determination image pattern with light illuminanceinformation set corresponding to the fake-determination image pattern;and a fingerprint analyzer configured to perform the fingerprintauthentication by comparing second sensing data corresponding to thefingerprint sensing area except the first pattern with registeredfingerprint data.
 42. The display device of claim 40, wherein thefingerprint detector includes: a pattern controller configured togenerate the fake-determination image pattern such that the firstpattern is included in the fingerprint sensing area; a fake fingerprintdetector configured to perform fake fingerprint determination bycomparing first sensing data corresponding to the first pattern of thefake-determination image pattern with light illuminance information setcorresponding to the fake-determination image pattern; and a fingerprintanalyzer configured to perform the fingerprint authentication bycomparing second sensing data corresponding to the fingerprint sensingarea with registered fingerprint data.
 43. The display device of claim42, wherein the fingerprint detector further includes: a memoryconfigured to store the light illuminance information corresponding tothe fake-determination image pattern and the registered fingerprintdata; and a use approval determiner configured to finally determinewhether use of the display device is to be approved, based on a resultof the fake fingerprint determination and a result of the fingerprintauthentication.
 44. The display device of claim 42, wherein the patterncontroller randomly changes the fake-determination image patterndisplayed on the display panel in a predetermined period.
 45. Thedisplay device of claim 42, wherein the pattern controller generates thefake-determination image pattern in a first period, and suspends thegeneration of the fake-determination image pattern in a second period.46. The display device of claim 45, wherein the fake fingerprintdetector performs the fake fingerprint determination by using the firstsensing data in the first period, and wherein the fingerprint analyzerperforms the fingerprint authentication by using the second sensing datain the second period.
 47. A method for driving a display device, themethod comprising: displaying a first image including user convenienceinformation through a display panel, the user convenience informationincluding a first pattern of a fake-determination image pattern;generating sensing data corresponding to a fingerprint sensing area byusing a photoelectric sensor; and determining whether a sensedfingerprint corresponding to the sensing data is a fake fingerprint bycomparing expected sensing light illuminance information based on thefirst image with sensed light illuminance information of the sensingdata.
 48. The method of claim 47, wherein the user convenienceinformation includes an indication image indicating the fingerprintsensing area, and wherein the indication image includes the firstpattern.
 49. The method of claim 48, wherein, when the display panel ispower-on, the first image is displayed based on the power-on of thedisplay panel.
 50. The method of claim 48, wherein the display paneldisplays a general image having a first refresh rate in a first mode,and displays a power-saving image having a second refresh rate smallerthan the first refresh rate in a second mode, and wherein thepower-saving image includes the first image.
 51. The method of claim 48,further comprising displaying a second image in which light is emittedin the entire fingerprint sensing area, based on a touch input.
 52. Themethod of claim 48, further comprising: performing fingerprintauthentication by comparing the sensing data with registered fingerprintdata; and determining whether use of the display device is to beapproved, based on a result of the fingerprint authentication and aresult of fake fingerprint determination.